WATER SUPPLY AND QUALITY IN THE PRAIRIES: A CASE STUDY OFCONFLICTS AND RESOLUTIONS

摘要

This talk highlights a case-study of Ridge Reservoir (RR), a small impoundment in the StMary River Irrigation District (S. Alberta), as a typical example of the growing water management issuesarising in the rural Prairies. Drought, extensive agriculture and irrigation, and watershed development/mismanagement have increased the potential for conflicting interests. Originally constructed for irrigationmanagement, RR is now an important domestic supply, recreational area, commercial and sports fishery,and waterfowl and wildlife habitat. Historically, a high flushing rate maintained riverine conditions and lowbiological productivity in RR despite high agricultural nutrient loading. A recent (1995) hydro diversion of>80% of the inflow has radically impacted flushing and hydrodynamics and raised local concerns withwater quality and safety, algal blooms, animal operations and land-use practices and highlighted thecritical need for stewardship and watershed management. The establishment of the Ridge ReservoirCommittee (RRC) in 2003 was an important step towards the resolution of these issues. Through thedirect involvement of local stakeholders, federal, provincial and municipal government and health agenciesand universities, the RRC has undertaken a collaborative study of the reservoir and drainage basin to i)assess key physical, chemical and biological processes contributing to water quality concerns, algalgrowth and the potential for toxic cyanobacteria; and ii) use this information to develop a long term waterprotection plan, increase public awareness and facilitate the implementation of best managementpractices.